In array substrates of display devices, gate driving circuits (GOAs, Gate-drivers On Array, i.e., gate driving circuits integrated on the array substrate) have been largely used. When a display panel is tested, testing of the gate driving circuits is an important part of the entire testing process. Control signals for the gate driving circuits include a high-level signal VGH (gate turn-on voltage) and a low-level signal VGL (gate turn-off voltage). In the prior art, a control signal generating circuit of the gate driving circuit mostly uses operational amplifiers to achieve conversion between the high-level signal VGH and the low-level signal VGL. However, when the gate driving circuit needs rapidly-changing control signals, such method of using operational amplifiers to provide control signals cannot meet the requirement.
Therefore, it has become a necessity to provide a control signal generating circuit for the gate driving circuit, which can achieve rapid conversion between the high-level signal and the low-level signal.